[Bridge Business Card]

　　 Address: Tongzi River Bridge is located at the junction of Renhuai City and Tongzi County. It is a double tower single span steel truss girder suspension bridge across Tongzi River, an important tributary in the upstream of Chishui River basin, connecting Renhuai City and Tongzi County. It is the only special bridge with complex technology on Jin Ren Tong Expressway.

　　 Features and innovation of the bridge:

Tongzi River Bridge on Jinren Tongtong Expressway is a steel truss girder suspension bridge with a total length of 1422 meters and a main span of 965 meters. The bridge deck is about 365 meters away from the river valley. The anchorage system adopts both tunnel anchors and gravity rock socketed anchors. The high and low towers on both banks adopt the form of pile group foundation and expanded foundation, and the design of pile free foundation is adopted in the construction of Renhuai'an bridge tower, It is the first long-span suspension bridge in the world with high and low towers designed with pile free foundation. The main cable is made of 1960Mpa high-strength galvanized aluminum parallel steel wire (the number of cable strands is optimized from 114 to 91). The steel truss beam is designed as a corbel, and the permanent suspension points are suspended outside the main truss (the width of the steel bridge deck is 29m, the spacing between the suspension points is 26m, and the spacing between the main trusses is 23.5m). 

　　 Interview with builders:

　　 Luo Huanbao: Solve technical problems and see the long dragon leap

The cold wind in early spring blows slowly, and wisps of fog gather and disperse. The magnificent bridge towers, thin tower cranes, red main cables, pure white slings, and the Tongzi River Bridge, whose main body has been basically completed, are looming in the thick fog. The steel dragon is riding on the clouds, supporting a new main road connecting Tongzi County and Renhuai City.

"At present, about 95% of the project construction tasks have been completed, and the construction of the remaining ancillary structures is expected to be completed by the end of the year. The whole line is expected to be open to traffic by the middle of 2024. At that time, the travel distance from Renhuai City to Tongzi County will be greatly shortened, and the economic and social development of the two places will add new wings." As the chief engineer of the Project Department of Section VII of Jinrentong Expressway, Luo Huanbao is familiar with the construction of Tongzi River Bridge.

In March 2019, Luo Huanbao, 25, as the technical director of the project, entered the seventh section project of Jinrentong Expressway and participated in the construction of this unique special bridge with complex technology.

"The bridge anchorage system of Tongzi River Bridge adopts both tunnel anchor and gravity rock socketed anchor, and the high and low towers on both banks adopt the form of pile group foundation and expanded foundation, which is the first structure combination in China." Luo Huanbao introduced that using this structural form is also an unavoidable choice.

Tongzi River, as an important tributary of Chishui River, has high requirements for green construction. Therefore, the Project Department always puts green environmental protection and low pollution in the first place during the construction process to minimize the damage to the surrounding ecological environment. At the same time, in the construction of Renhuai Bank, due to the particularity of karst landform, there is a large karst cave underground. To ensure safe construction, we finally adopted the pile group foundation design for the tower.

"In addition, according to the implementation of the project, we finally decided to change the main cable steel wire from the original 1860Mpa galvanized aluminum parallel steel wire to the 1960Mpa high-strength galvanized aluminum parallel steel wire, reduce the number of cable strands, significantly reduce the scale of tunnel anchors, shorten the construction period, and improve the durability of zinc aluminum alloy coated steel wire by about 30% compared with ordinary galvanized steel wire," Luo Huanbao said.

The landing and completion of a major project is not as easy as ordinary people see. As the chief engineer of the project, Luo Huanbao worked together with all the project owners, After nearly three years of hard work, the dream of Tongzi River Bridge leaping across the two sides became reality.

"Years of hard work has paid off the best. Not only have I grown from the technical director of the project to the chief engineer of the project, but also I have witnessed the bridge from the design drawings to the cross-strait, towering between heaven and earth." Luo Huanbao said with emotion, whenever the clouds and fog disappear and the bridge shows its majesty from the fog, I have a pride that is difficult to express in words, Tongzi River Bridge, one of the top 20 bridges in the world, was built by me!

See more: 【 Special 】

Tianyan News Reporter of Guizhou Daily

Text/Video: Yang Yufeng, Zhang Shaodong, Liu Qing, Jia Zhi

Poster Design Nie Jingwen

　　 Editor Liu Juan

Second instance Yang Tao

Third instance Min Jie